Nano n-propylsulfonated γ-Fe2O3 as a new sulfonated nanomagnetic iron oxide was synthesized directly through ring opening reaction of 1,3-propanesultone with nano magnetic γ-Fe2O3 and used as magnetically recyclable heterogeneous catalyst for the efficient one-pot synthesis of β-phosphonomalonates. The catalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least five times without significant degradation in the activity.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (118 K)Download as PowerPoint slideHighlights► In this paper, nano n-propylsulfonated γ-Fe2O3 (NPS-γ-Fe2O3) was synthesized. ► NPS-γ-Fe2O3 was synthesized directly by ring opening reaction of 1,3-propanesultone. ► NPS-γ-Fe2O3 is a new sulfonated nanomagnetic iron oxide. ► NPS-γ-Fe2O3 was applied as a new catalyst for the synthesis of β-phosphonomalonates. ► NPS-γ-Fe2O3 was isolated from the reaction mixture by magnetic decantation.